Na(+) regulation by combined nitrogen in Azolla pinnata-Anabaena azollae symbiotic association during salt toxicity

To study the regulation of Na(+) ion by combined-N sources in Azolla pinnata-Anabaena azollae, Na(+) influx, intracellular Na(+) and Na(+) efflux were investigated in the presence of different N-sources (N(2), NH(4)(+), NO(3)(-) and urea) and various NaCl concentrations. Sodium influx by Azolla pinnata fronds was minimum in the presence of NO(3)(-). Almost identical levels of intracellular sodium, although less than N(2) and NH(4)(+) incubated fronds were observed in the presence of NO(3)(-) and urea. Efflux of sodium was minimum in urea and NO(3)(-) grown fronds. A low residual sodium was observed in the fronds incubated in NO(3)(-) and urea supplemented media. Results suggest that nitrate and urea curtailed the entry of sodium, reduced salt toxicity maximally by maintaining the minimum level of sodium and also conserved energy due to slow influx and efflux of Na(+) within the fronds during salt shock and the process of adaptation.     

Chordoma of the Lumbar Spine Presenting as Sciatica and Treated with Vertebroplasty

The lumbar spine is a less common location for chordoma. Here we describe a 44-year-old woman presenting with pain due to a L4 vertebral expansile lesion that caused significant canal stenosis and neural foraminal compromise. Vertebroplasty was performed and resulted in immediate pain relief. For patients with painful lumbar chordoma who are unwilling to undergo surgery, vertebroplasty can play a palliative role as in patients with other vertebral lesions. Treating pain and stabilizing vertebra by way of vertebroplasty in a case of chordoma has not yet been reported.